Continuous-time general link transmission model with simplified fanning, Part II: Event-based algorithm for networks. (August 2019)

• Record Type: Journal Article
• Authors: Raadsen, Mark P.H.; Bliemer, Michiel C.J.
• Is Part Of: Transportation research. Volume 126(2019)
• Page Start: 471
• Page End: 501
• Publication Date: 2019-08
• Subjects: Continuous-time -- Grid free -- Event-based -- Solution scheme -- Link transmission model -- Macroscopic traffic flow -- Dynamic traffic assignment -- Network loading -- Simplified fanning; Transportation -- Research -- Periodicals; Transportation -- Mathematical models -- Periodicals
• DOI: 10.1016/j.trb.2018.01.003
• Languages: English
• ISSNs: 0191-2615

Abstract

Highlights: Event-based solution scheme for the (general) link transmission model. On-the-fly inner linearization technique to simplify expansion fans in a general network setting. Event-based multi-commodity support framework for different types of commodities such as path based or departure time period based approaches. Within iteration route choice support in an event-based macroscopic network loading setting. Case studies on general network demonstrating suitability and feasibility of the proposed solution scheme for large scale planning purposes. Abstract: In this paper a novel solution algorithm is proposed for solving general first order dynamic network loading (DNL) problems in general transport networks. This solution algorithm supports any smooth non-linear two regime concave fundamental diagram and adopts a simplified fanning scheme. It is termed eGLTM (event-based General Link Transmission Model) and is based on a continuous-time formulation of the kinematic wave model that adapts shockwave theory to simplify expansion fans. As the name suggests eGLTM is a generalisation of eLTM, which is a special case that solves the simplified first order model assuming a triangular fundamental diagram. We analyse the impact of modelling delay in the hypocritical branch of the fundamental diagram to assess the differences between the two models. In addition, we propose an additional stream of mixture events to propagate multi-commodity flow in event based macroscopic models, which makes both eLTM and eGLTM suitable for dynamic traffic assignment (DTA) applications. The proposed solution scheme can yield exact solutions as well as approximate solutions at a significantly lesser cost. The efficiency of the model is demonstrated in a number of case studies. Furthermore, different settings for our simplified fanning scheme are investigated as well as an extensive analysis on the effect of including route choice on the algorithms computational cost. Finally, a large scale case study is conducted to investigate the suitability of our newly proposed model in a practical context and assess its efficiency. In this study comparisons between eLTM and eGLTM are included to demonstrate the impact of aforementioned generalisation as well as the multi-commodity extension that is proposed.